Thermocouple principle

KKST patch plug-in active passive crystal oscillator hot sale 24.576000MHZ

In the industrial production process, temperature is one of the important parameters that need to be measured and controlled. At present, more temperature measuring components are used as thermocouples. Let’s follow the Xiaobian to understand the thermocouple principle . See how the thermocouple completes the temperature measurement function~

First, the principle of thermocouple - - Introduction

Thermocouple, the English name is thermocouple, is a commonly used temperature measuring component that performs temperature detection by converting a temperature signal into an electrical signal. Thermocouples can be roughly divided into standard thermocouples and non-standard thermocouples. Their shapes are very different, but they are composed of hot electrodes, insulating sleeve protection tubes and junction boxes, and are often equipped with records. Auxiliary equipment such as instruments, electronic regulators, and display instruments. Since the thermocouple belongs to the active sensor, it does not need an external power supply when it is used, and has the advantages of simple structure, convenient operation, high precision, wide range, small inertia, etc., and has been widely used.

Second, the principle of thermocouple

The thermocouple mainly performs the related function according to the "thermoelectric effect". The thermoelectric effect refers to a closed loop composed of two different conductors. It is assumed that one end is the A end, the temperature is Ta, the other end is the B end, and the temperature is Tb. When Ta and Tb are not equal, there is a current flowing in the loop, thus generating an electromotive force. The magnitude of the electromotive force is affected by the temperature difference between the ends A and B. We call this phenomenon a "thermoelectric effect" and form a loop of the two conductors. Called "thermocouple", the electromotive force generated is called "thermal electromotive force".

During the thermocouple temperature measurement process, we refer to the end of the two conductors in the closed loop as the "free end", so that it is in the constant temperature state, and the other end is called the "working end", which is used to connect the object to be tested and when the object to be tested is connected. When the closed loop is formed, the thermoelectromotive force is generated due to the influence of the temperature difference, so the working terminal temperature can be obtained by the thermoelectromotive force and the free end conductor temperature to complete the function of the temperature measurement.

Third, the principle of thermocouple - - Features

1. It has strong seismic performance and pressure resistance, and has fast response speed and long service life;

2, the structure is simple, mainly composed of two different wires;

3, is an active sensor, no additional power supply when measuring temperature, easy to use;

4. It is a non-contact temperature measuring component, which is not affected by other media and has high precision;

5, a wide range of applications, not only the type of shape is suitable for any environmental conditions, and it is suitable for the temperature range of -269 degrees to 2800 degrees.

Thermocouple principle related articles